The present invention relates to cartons generally formed of paperboard and capable of holding liquid products. Typical cartons have a core structural layer of paperboard providing the carton's strength and rigidity. A layer of aluminum foil is adhered to one surface of the paperboard and serves as a barrier layer against passage of contaminants into the package. Both outer surfaces of the paperboard/foil combination are then coated with heat sealable plastic. While a number of specific constructions are known, it is generally accepted practice to close the carton openings with seals wherein surfaces of the plastic which face the interior of the carton are brought into face-to-face contact along opposing edges and sealed together, in most cases forming a fin. Such a structure (using an interior plastic sealing layer) is disclosed in U.S. Pat. No. 4,327,833 to Kuchenbecker.
That patent discloses an improved carton opening that does not require the use of cutting means (knives, scissors, etc.) to open the carton. The patented carton has a fin seal with two opposing edge flaps projecting above lines of weakness. The edges are adhered together with the lines of weakness in registry to form a protecting member that is torn at the line of weakness to open the carton. Such liners render the carton liquid tight but complicate manufacture of the carton and make opening such cartons difficult. Because such cartons are mass produced and should be liquid tight, moisture resistant, easily opened and readily manufactured, there exists a demand for improved cartons of this type, especially those having only a plastic coating rather than a separate plastic liner.
Therefore, it is a principal object of the present invention to provide a carton having a readily opened pour spout that is liquid tight and moisture resistant.
It is a further object of the invention to provide a carton with a pour spout that can be readily manufactured in bulk quantities.
It is an additional object of the present invention to provide a carton having a pour spout opened by tearing along a line of weakness that forms an edge on the spout that resists dribbling of liquid poured from the spout.
Other objects of the invention will be described in the description of the preferred embodiment or may be apparent therefrom.